1. Field of the Invention
The present invention relates to an LED package structure and a method for manufacturing the same, in particular, to an LED package structure with standby bonding pads for increasing wire-bonding yield and a method for manufacturing the same.
2. Description of Related Art
The invention of the lamp greatly changed the style of building construction and the living style of human beings, allowing people to work during the night. Without the invention of the lamp, we may stay in the living conditions of ancient civilizations.
Various lamps such as incandescent bulbs, fluorescent bulbs, power-saving bulbs and etc. have been intensively used for indoor illumination. These lamps commonly have the disadvantages of quick attenuation, high power consumption, high heat generation, short working life, high fragility, and being not recyclable. Further, the rapid flow of electrons (about 120 per second) through the electrodes of a regular fluorescent bulb causes an unstable current at the onset of lighting a fluorescent bulb, resulting in a flash of light that is harmful to the sight of the eyes. In order to eliminate this problem, a high frequency electronic ballast may be used. When a fluorescent or power-saving bulb is used with high frequency electronic ballast, it saves about 20% of the consumption of power and eliminates the problem of flashing. However, the high frequency electronic ballast is not detachable when installed in a fluorescent or power-saving bulb, the whole lamp assembly becomes useless if the bulb is damaged. Furthermore, because a fluorescent bulb contains a mercury coating, it may cause pollution to the environment when thrown away after damage.
Hence, LED lamp or LED tube is created in order to solve the above-mentioned questions of the prior lamp. Referring to FIG. 1, the LED package structure of the prior art includes a plurality of LED chips 20. The positive electrode (not shown) and the negative electrode (not shown) of each LED chip 20 respectively correspond to one positive pad P and one negative pad N. Hence, when one end of a wire W does not correctly connect with the positive pad P or the negative pad. N (it means that the wire W does not electrically connect with the positive pad P or the negative pad N (such as floating solder)), the manufacturer firstly needs to clean solder splash on the surface of the positive pad P or the negative pad N, and then making the same end of the wire W bond on the clean surface of the positive pad P or the negative pad N again. Therefore, the prior art increases wire-bonding time (decreases wire-bonding efficiency) and decreases wire-bonding yield.